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Screening of newborn babies in England is being expanded from this week (5 January) to include four more genetic disorders—homocystinuria, maple syrup urine disease, glutaric aciduria type 1, and isovaleric acidaemia.

About half of England already screens for these conditions, having taken part in a pilot study, and the screening will now be offered to newborns in the rest of the country. Wales will begin screening for these conditions early in 2015, and the other two countries of the United Kingdom have yet to …